History of the Peloponnesian War

On the contrary, they supposed these troops to be their own men, for Demosthenes had purposely put the Messenians in front and directed them to accost the enemy in the Doric dialect, thus getting themselves trusted by the outposts; besides, they were indistinguishable to the sight, since it was still dark. So they fell upon the army of the Ambraciots and put them to rout, slaying the majority of them on the spot;

the rest took to flight over the mountains.

But as the roads had already been occupied, and as, moreover, the Amphilochians were well acquainted with their own country and were light infantry opposing heavy-armed troops, whereas the Ambraciots were ignorant of the country and did not know which way to turn, under these circumstances the fleeing men fell into ravines and into ambushes which had previously been set for them and perished.